Integrated circuit and method for avoiding starvation of data

Abstract

The invention provides a router which can be deployed in a network on an integrated circuit. The router is capable of processing input data belonging to multiple traffic classes. The router can further guarantee, under admissible traffic, that all input data are processed and output adequately at an acceptable cost. The invention relies on the perception that the problem of contention is constituted by two more specific problems: input contention and output contention. The problem of input contention does not occur anymore, because the switch comprised in the router is designed such that it can serve multiple queues coupled to input ports simultaneously. The problem of starvation, caused by a continuous preference of high priority traffic to low priority traffic, is solved by allowing to serve queues containing data from low priority traffic classes simultaneously with queues containing data from high priority traffic classes.

1 . An integrated circuit comprising a network, the network comprising a plurality of routers at least one of the routers comprising a plurality of input ports arranged to receive input data corresponding to at least two traffic classes, the routers further comprising a plurality of queues the queues being arranged to store input data corresponding to a single traffic class, wherein the input ports are coupled to at least two of the queues, the routers further comprising a switch characterized in that the switch is arranged to receive input from the plurality of queues simultaneously.  
     
     
         2 . An integrated circuit as claimed in  claim 1 , wherein a first selection of the queues is arranged to store input data corresponding to a high priority traffic class, and wherein a second selection of the queues is arranged to store input data corresponding to a low priority traffic class.  
     
     
         3 . An integrated circuit has claimed in  claim 2 , wherein the first selection is deployed to provide guaranteed communication services in the network, and wherein the second selection is deployed to provide best-effort communication services in the network.  
     
     
         4 . An integrated circuit as claimed in  claim 1 , further comprising a controller which is coupled to the input ports and coupled to the switch the controller comprising a plurality of arbiters, wherein the arbiters of at least one of the traffic classes implement a predetermined schedule.  
     
     
         5 . An integrated circuit as claimed in  claim 1 , wherein the switch comprises a plurality of multiplexers, each multiplexer being coupled to an output port, and each one of the multiplexers being arranged to accept as input the input data stored in the queues.  
     
     
         6 . A method for avoiding starvation of data in an integrated circuit comprising a network, the network comprising a plurality of routers at least one of the routers comprising a plurality of input ports receiving input data corresponding to at least two traffic classes, the routers further comprising a plurality of queues wherein the queues store input data corresponding to a single traffic class, the input ports being coupled to at least two of the queues, the routers further comprising a switch, characterized in that the switch receives input from the plurality of queues simultaneously.